<template>
  <div id="cesiumContainer"></div>
</template>

<script>

  export default {
    name: 'SceneUpdateEvent',
    mounted() {
      let viewer = this.initCesium();

      this.addSceneUpdateEvent(viewer);
    },
    methods: {
      initCesium: function () {
        Cesium.Ion.defaultAccessToken = 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiJkZjg4ZjljZC1mZGM3LTRlZjEtYjg3MC00MjZkNGU3YjI5ZWUiLCJpZCI6MTU5NTIsImlhdCI6MTYwNTE0ODM5OX0.LjxeKrgAo7Ksk8405kSAhYwF0nKcF2w2DGJnKHh51N8';
        let viewer = new Cesium.Viewer('cesiumContainer', {
          animation: true,
          baseLayerPicker: false,
          fullscreenButton: false,
          geocoder: false,
          homeButton: false,
          infoBox: false,
          sceneModePicker: false,
          navigationHelpButton: false,
          scene3DOnly: true,
          timeline: true,
          selectionIndicator: false,//是否显示选取指示器组件
          shouldAnimate: true,     //自动播放动画控件
          shadows: true,//是否显示光照投射的阴影
          terrainShadows: Cesium.ShadowMode.RECEIVE_ONLY,//地质接收阴影
          sceneMode: Cesium.SceneMode.SCENE3D,
          imageryProvider: new Cesium.ArcGisMapServerImageryProvider({
            url: "https://server.arcgisonline.com/arcgis/rest/services/World_Imagery/MapServer?f=jsapi"
          }),
          terrainProvider: new Cesium.EllipsoidTerrainProvider()
        });
        viewer._cesiumWidget._creditContainer.style.display = "none";  //	去除版权信息
        return viewer;
      },
      addSceneUpdateEvent(viewer) {

        Cesium.Math.setRandomNumberSeed(3);

        //Set bounds of our simulation time
        var start = Cesium.JulianDate.fromDate(new Date(2015, 2, 25, 16));
        var stop = Cesium.JulianDate.addSeconds(
          start,
          360,
          new Cesium.JulianDate()
        );

        //Make sure viewer is at the desired time.
        viewer.clock.startTime = start.clone();
        viewer.clock.stopTime = stop.clone();
        viewer.clock.currentTime = start.clone();
        viewer.clock.clockRange = Cesium.ClockRange.LOOP_STOP; //Loop at the end
        viewer.clock.multiplier = 10;

        //Set timeline to simulation bounds
        viewer.timeline.zoomTo(start, stop);

        //Generate a random circular pattern with varying heights.
        function computeCirclularFlight(lon, lat, radius) {
          var property = new Cesium.SampledPositionProperty();
          for (var i = 0; i <= 360; i += 45) {
            var radians = Cesium.Math.toRadians(i);
            var time = Cesium.JulianDate.addSeconds(
              start,
              i,
              new Cesium.JulianDate()
            );
            var position = Cesium.Cartesian3.fromDegrees(
              lon + radius * 1.5 * Math.cos(radians),
              lat + radius * Math.sin(radians),
              Cesium.Math.nextRandomNumber() * 500 + 1500
            );
            console.log(position)
            property.addSample(time, position);

            //Also create a point for each sample we generate.
            viewer.entities.add({
              position: position,
              point: {
                pixelSize: 8,
                color: Cesium.Color.TRANSPARENT,
                outlineColor: Cesium.Color.YELLOW,
                outlineWidth: 3
              }
            });
          }
          return property;
        }

        //Compute the entity position property.
        var position = computeCirclularFlight(-112.110693, 36.0994841, 0.03);

        //Actually create the entity
        var entity = viewer.entities.add({
          //Set the entity availability to the same interval as the simulation time.
          availability: new Cesium.TimeIntervalCollection([
            new Cesium.TimeInterval({
              start: start,
              stop: stop
            })
          ]),

          //Use our computed positions
          position: position,

          //Automatically compute orientation based on position movement.
          orientation: new Cesium.VelocityOrientationProperty(position),

          //Load the Cesium plane model to represent the entity
          model: {
            uri: "http://localhost:8888/model/SampleData/models/CesiumAir/Cesium_Air.glb",
            minimumPixelSize: 64
          },

          //Show the path as a pink line sampled in 1 second increments.
          path: {
            resolution: 1,
            material: new Cesium.PolylineGlowMaterialProperty({
              glowPower: 0.1,
              color: Cesium.Color.YELLOW
            }),
            width: 10
          }
        });

        //实时渲染
        viewer.scene.postRender.addEventListener(function () {


        });

        let hpRange = new Cesium.HeadingPitchRange();
        viewer.scene.preRender.addEventListener(function () {
          if (entity) {
            hpRange.heading = Cesium.Math.toRadians(-90);
            hpRange.pitch = Cesium.Math.toRadians(-45);
            hpRange.range = 100;
            var center = entity.position.getValue(viewer.clock.currentTime);
            if (center) {
              viewer.camera.lookAt(center, hpRange);
            }
          }
        });
        viewer.scene.screenSpaceCameraController.enableRotate = true
        viewer.scene.screenSpaceCameraController.enableTranslate = true
        viewer.scene.screenSpaceCameraController.enableZoom = true
        viewer.scene.screenSpaceCameraController.enableTilt = true
      }
    }
  }
</script>
<style scoped>
#cesiumContainer {
  height: 100%;
  width: 100%;
  background-color: red;
}
</style>
